Once, more than several years ago, while high on LSD, I walked across a bridge over the Mississippi River. Rather than becoming anxious about the drop, I found myself in an unusually calm state of mind as I approached the center of the span, which seemed like a giant runway arching up to cloud level at some kind of colossal cosmic airport. It was around then that I started to become aware of a distinct impression as I walked along. Or rather, it was perhaps just the same impression as always, but something about it had definitely changed in a profound, yet fairly indescribable way.
Be that as it may, I'll try to explain it: quite suddenly I ceased to remain aware of myself as a person slowly walking along across the top surface of a stationary bridge. Instead - as one might have to say it - there was a bridge that was walking itself along beneath my feet, rotating slowly under me, while I remained entirely stationary above it, save for the repetitive pedaling motion of my legs.
We know, by now, that all motion is relative to the observer. Intuitively, I might speculate that this "illusion" was caused mainly by the specific set (or lack) of visual cues typically encountered when standing or walking on a tall, narrow structure, in addition to the profoundly disassociative effects of the acid. But the experience has nevertheless stayed with me for reasons I can't entirely explain. It seems to me, even now, that the way I looked at motion then wasn't fundamentally wrong.
After all, what exactly is an observer?
